[llvm] [AMDGPU][NewPM] Port SIShrinkInstructions to new pass manager. (PR #106967)

[Christudasan Devadasan via llvm-commits]

cdevadas wrote:

### Merge activity

* **Sep 3, 1:21 AM EDT**: @cdevadas started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/106967).


https://github.com/llvm/llvm-project/pull/106967